Extrusion press



June 22, 1965 E. MULLER EXTRUSION PRESS Filed June 22, 1962 United States Patent 7" 3 Filed June 22, 1962, Ser. No. 204,378 4 Claims. (Cl. 72-265) The present invention relates to anextrusion press for producing hollow or tubular members and more particularly to a hydraulic press of this type in which the driving cylinder for the piercing mandrel is located outside the main pressure cylinder and is rigidly connected to the piston of this cylinder.

Hydraulic metal tube presses are already known in which the driving cylinder providingthe driving of the piercing mandrel is disposed axially behind the main cylinder and is rigidly connected to the press frame. In such arrangements the mandrel drive depends on the movement of the main pressure ram. In a metal tube press of that type the mandrel stroke must be of such a length that it is capable of carrying out the stroke of the pressure ram as Well as of the additional stroke for piercing the block. For this reason, the mandrel drive cylinders and return mechanisms must be made of a corresponding size and therefore these presses have substantial dimensions either in length or in height. a y

In other prior art presses of this type, the mandrel drive has been mounted in such a manner in the'main pressure piston that it serves simultaneously as cylinder for the mandrel drive piston or so that it may receive'this ment is usually required for the mandrel rod audit is generally located infront of the main pressure. cylinder. This mandrel guide takes up a substantial amount of space 3,l9il,l2 Patented June 22, 1965 ing mandrel which are located behind the main pressure piston are made. freely accessible from all sides so that in the event'of disturbances or of a breakdown, or for exchanging parts, no difiicult or time-consuming repair work will be necessary. a

According to a main feature of the invention the connection between the driving cylinder for producing the movement of the piercing mandrel and the main pressure piston consists of an extension of the main pressure piston passing rearwardly through the main pressure cylinder, This extension serves simultaneously as a guide for the mandrel rod and is connected preferably over a plurality of columns to the driving cylinder of the mandrel. In

, this case the arrangement is preferably so designed that piston within its structure. This known arrangement has a and due to its length requires a substantial interval bea tween the cylinder and the crossbeam in order to provide still enough room to insert the metal blocks. This necessitates very long frame columns or a frame structure of great length which leads to greater dimensions of the frame construction and thus also to a considerable increase in which is independent of the main pressure piston, presenting the advantage of a clear unencumbered construction and easy accessibility of the driving elements combined with the additional advantage of avoiding the long strokes for the driving cylinder of the mandrel and the return mechanism of the prior art construction, whereby a substantial reduction of size and weight of the press is obtained.

According to the invention the driving cylinder for producing the actuation of the mandrel is mounted for movement outside the main pressure cylinder and is rigidly connected to the main pressure piston. By means of this connection the stroke distance of the driving piston for the piercing mandrel may be limited to the extent necessary for the piercing stroke because its driving cylinder carries out all the movements of the main pressure ram fixed to the main pressure piston. At the same time this novel construction provides an additional advantage in that the driving elements for producing the movement of the piercthe extension of the main pressure piston terminates in a crossbeam which is connected through columns to a crosshead which carries the mandrel driving cylinder. By means of the column construction between the 'crossoeam and the crosshead, the free accessibility of the mandrel drive is realized in a particularly advantageous manner. A further advantage of the invention resides in the fact that due to the constructionally clear arrangement between the main drive and the mandrel drive during the extrusion of solid bars instead of tubes, the portion of the mandrel drive may be easily uncoupled and need thus not always be carried along by the main pressure piston.

Further objects and advantages of the present invention will become apparent from the following description taken in combination with the attached drawing in which the single figure shows in longitudinal sectional elevation a inwardly of the die 4-, its bore 5a. communicating and be- 7 ing aligned with the opening of the die and with the 'extrusion opening 3a. As shown in the drawing, a metal block or billet'fi to bepierced and extruded is. located in front of the bore 5a of the billet container 5. .The main pressure piston 8 is hollow and has a hollow extension at one end which constitutes a ram 7 for engaging the billet and for extruding it through the die. As shown in the drawing, ram 7 is located in its extreme end position to the left, the main pressure piston 8 having moved as far as possible into cylinder 1. The main pressure piston has a tubular extension 8a at the other end which passes in sliding engagement through a central opening provided for that purpose in the end wall In of main pressure cylinder 1. The extension 8a terminates in a transverse plate or crossbeam 8b which is connectedby means of columns 9 to a crosshead it This crosshead 19 has a cylindrical rearward extension which constitutes a driving cylinder 11 in which a driving piston 12 is received which is adapted to actuate the piercing mandrel 14. In the particular arrangement shown, the driving cylinder 11 for the piercing mandrel carries out all the movements of the main pressure piston.

The driving cylinder 11 is shown as an integral part of the crosshead 1i but it is understood that it may be a separate member which is fixed in any suitable manner to the crosshead. The driving piston 12 terminates in a disc or head 12b of larger diameter than the piston body or shaft, the head portion of the piston being in sliding engagement with the inner Wall of cylinder 11. The piston head may thus be employed to return the piston into the starting position. The driving piston 12 is connected over the mandrel rod 13 passing through the hollow cen- 1 ter. of the main pressure piston to the piercing mandrel 14- which extends partly through the center of the main' pressure piston and partlythrough the center of the ram" '7 which isshown as being integral with the main pressure piston. The piston extension 8a serves as a guide for'the mandrel rodr13. I

- The crosspiece 12a of driving piston 12is provided with adjustable .stops 17which are adapted to pass through suitable bores 15 in the crossbeam 8b. and strike corresponding buffers 16 fixed to the end wall of the main pres- .sure cylinder 1. These stops 17 serverto' set the position of the mandrel in thedie' 4 whenthe pressing operation is carried out while the mandrelis stationary. V In operation, assuming the pistons 12'and;8,to be .in

their extreme end positions in which the ram 7 and the mandrel 14 are withdrawn from the receiver 5 a' metal 5 block 6 is inserted intov the receiver Sin the customary H r manner; Pressure medium is introduced'into the cylinder 11 behind the piston head 12b through a pipe or'other suitable conduit 13 connected to the end of this cylinder i as shown in dotted lines. The pressure medium causes the;piston. 12 "to move .tothe right thereby forcing the mandrel 14 into the metal block to piercea hole there through. The :forward movement of the piston. 12Jand mandrel 14 is continued until the front end of the mandrel projects into the opening of the die 4; The stopsl'l 'are so adjusted as to strike against the buffers 16 in this position of the mandrel thereby preventing. further forward movement thereof. Pressure medium is then introduced to the left side of the piston 8 inthe main cylinder 1 and the main pistonwith the ram 7 is moved towards the right as shown in the'drawing'. During its forward movement i What is claimed is:

1. A press for extruding tubular members comprising in combination anabutment block having an extrusion opening therein, an extrusion die supported adjacent the inner face of said abutment block, a billet container mountedjadjace'nt said extrusion die and having a bore' communicating with said die and said extrusion opening, 50

a stationary pressure cylinder mounted in spaced relation 4 7 to said billet container and rigidly connected to said abutrnent block, said stationary pressure cylinder, having an having 'an opening therethrough, a first hollow piston 5 slideably received in said stationary pressure cylinder, a

hollow ram at one end' of'said first piston and adapted to slide in thebore of said billet container, a tubular extension at the other end of said first piston and slideable in the opening in said-remote end of said stationary cylinder,

'21 crossbeam fixed to'the end of said'tubular extensionya" :crosshead, rigidly connected in spaced relation to said erossbeam', a movable pressure cylinder rigidly connected to said crosshead, a second piston 'slideably received in said movable cylinder, a crosspiece fixed to said second. a

piston and disposed for movement between said crossbeam and said crosshead, means on said crosspiece for adjusting the stroke of'said second pistoma rod connected it'o said second piston and ,slideably received in said tubular. ex;

' tension, and a piercing mandrelconnected to said rodand' slideably received insaid'first piston and in said hollow ram, said first piston being operable independently of said j second piston to move said mandrel relative tosaid hollow.

ram into said billet container and said die, i

7 adjustable stops. a a, p

I 3."A press for extruding tubular members as defined in claim 1 wherein bufier means are fixed to said remote end buffermeans and with said elongate adjustable stops, said elongate adjustable stops being adapted topass; throug said openings to eng'age'said butler means. 7

4. A press forextruding tubular membersas defined in.

claim 1 wherein said crosshead is connectedr-tosaidcrossbeam by a plurality of spaced connecting columns.

References Cited by the Examiner 0 I :QUNrTE STATES PATENTS. A

888,299 [5/08 Benjamin 20.7 3 2,902,147 *9/59 Meier- 207-3 72,983,373 5 6 1 Wellsetal .207--j-3 FOREIGN PATENTS 395,906, 7/33 "Great Britain.

\ (WILLIAM J. STEPHENSON, Primary Examiner; 7 RICHARD J H. EANES, MICHAEL v. BRINDISLJ.

. V I Examiners.

open end facing said billetcontainer and a remote end 2'. A press for extruding tubular members as defined. j claim 1 wherein. said. means for adjusting the stroke of said second piston consist of axially'extendingelengate' 'ofsaid stationary pressure cylinder opposite saidncro'ssf beam, said crossbeam havingopenings aligned with said 7 

1. A PRESS FOR EXTRUDING TUBULAR MEMBERS COMPRISING IN COMBINATION AN ABUTMENT BLOCK HAVING AN EXTRUSION OPENING THEREIN, AN EXTRUSION DIE SUPPORT ADJACENT THE INNER FACE OF SAID ABUTMENT BLOCK, A BILLET CONTAINER MOUNTED ADJACENT SAID EXTRUSION DIE AND HAVING A BORE COMMUNICATING WITH SAID DIE AND SAID EXTRUSION OPENING, A STATIONARY PRESSURE CYLINDER MOUNTED IN SPACED RELATION TO SAID BILLET CONTAINER AND RIGIDLY CONNECTED TO SAID ABUTMENT BLOCK, SAID STATIONARY PRESSURE CYLINDER HAVING AN OPEN END FACING SAID BILLET CONTAINER AND A REMOTE END HAVING AN OPENING THERTHROUGH, A FIRST HOLLOW PISTON SLIDEABLY RECEIVED IN SAID STATIONARY PRESSURE CYLINDER, A HOLLOW RAM AT ON END OF SAID FIRST PISTON AND ADAPTED TO SLIDE IN THE BORE OF SAID BILLET CONTAINER, A TUBULAR EXTENSION AT THE OTHER END OF SAID FIRST PISTON AND SLIDEABLE IN THE OPENING IN SAID REMOTE END OF SAID STATIONARY CYLINDER, A CROSSBEAM FIXED TO THE END OF SAID TUBULAR EXTENSION, A CROSSHEAD RIGIDLY CONNECTED IN SPACED RELATION TO SAID CROSSBEAM, A MOVABLE PRESSURE CYLINDER RIGIDLY CONNECTED 